The present invention relates to an apparatus for evaluating the inner quality of vegetables and fruits for measuring the quality evaluation amount of the sugar degree, the ripening degree or the like of vegetables and fruits nondestructively to evaluate the inner quality, a method for warming-up operating and a method for measuring the inner quality in the apparatus.
There has been heretofore known a method of measuring the inner quality of vegetables and fruits nondestructively to evaluate by irradiating light from a light source on vegetables and fruits and applying spectral analysis to the reflecting light or transmission light.
As the apparatus to which the above method is applied, there has been known an apparatus installed on the floor of an inspection room or the like and placing vegetables and fruits on the place bed to measure and evaluate them (see Japanese Patent Laid-Open No. Hei 11-125593 Publication, etc.), or an apparatus installed on the selective line or the like and placing vegetables and fruits on the carrying conveyor to measure and evaluate them (see Japanese Patent Laid-Open No. Hei 11-337480 Publication, etc.).
However, the above-described conventional apparatuses are large in type and expensive, and small-scaled enterprisers were very hard to introduce them in terms of installation places, purchase expenses and so on. Further, when the apparatuses are once installed, their installation place cannot be changed easily, thus being inconvenient.
Further, in the apparatus placing vegetables and fruits on the place bed to measure and evaluate them, a cover for shielding disturbance light is disposed, and when the cover is closed, automatic measurement is carried out. It is, however, troublesome to close the cover separately, and it takes much time for measurement.
Further, a halogen lamp or the like as a light source has its service life, and if an over-current should flow, it would possibly be broken. In such a case, the lamp has to be replaced, but in the conventional apparatuses, the safety and the promptness in replacing work have not at all been taken into consideration.
Moreover, in such apparatuses as described, it requires a fixed time till the spectrum of a light source is stabilized after a power switch has been turned on. Unless the spectrum of the light source is stabilized, the inner quality of vegetables and fruits cannot be measured and evaluated with good accuracy.
From the foregoing, in the conventional apparatuses, when the apparatuses are started, the warming-up operation has been obliged for a period of time obtained by multiplying the time considered to be necessary by the safety rate, that is, a long period of time more than that required. Further, when the apparatuses are restarted, and also when the apparatuses are returned after the power failure, the warning-up operation for a period of time similar to that when the apparatuses are first started has been obliged.
Therefore, when the apparatuses are first started, an operator has to wait for a long period of time more than that required till measurement and evaluation are started, and when the apparatuses are restarted, and when returned after the power failure, the time required for restart and a period of time for the power failure have not at all been taken into consideration, and therefore, the entirely wasteful time has been included in the waiting time.
Further, the above-described conventional apparatuses are all large in type and expensive, which measure and evaluate a large quantity of the same kind and the same breed of vegetables and fruits. Therefore, the spectral strength of the light source and the measuring time corresponding to vegetables and fruits have been set in advance, and the reflecting light or the transmission light from vegetables and fruits have been measured merely for the measuring time.
The conventional large type and expensive apparatuses have been difficult to be introduced by small enterprisers in terms of the installation place, purchase expenses or the like, and a small type and inexpensive apparatus has been demanded. On the other hand, for the small type and inexpensive apparatus, there is demanded general-purpose properties that can measure and evaluate many kinds and many breeds of vegetables and fruits.
However, the strength of the reflecting light or the transmission light from vegetables and fruits differs greatly depending on the kind or breed of vegetables and fruits. In a case of vegetables and fruits whose optical strength is small (absorbance is large), it is necessary to make the measuring time longer and maintain the S/N ratio in order to secure the measuring accuracy. Therefore, in a case where the measuring time is made to correspond to vegetables and fruits whose optical strength are small, the measuring time is surplus for vegetables and fruits whose optical strength are large.
On the other hand, in a case where the measuring time is made to correspond to vegetables and fruits whose optical strength is small, the resolution of an A/D converter has to be lowered in order to secure the dynamic range in the measurement of the optical strength, and when the resolution of an A/D converter is intended not to be lowered, an amplifier having a multistage gain is necessary.
The present invention has been accomplished in view of the problem as noted above with respect to prior art, and the object of the present invention is to provide a very convenient apparatus for evaluating the inner quality of vegetables and fruits, which is small in type and inexpensive, can be introduced easily by small-scaled enterprisers, can change the installation place easily, and in which measurement can be carried out easily, the measuring time can be shortened, and further, the safety and promptness in the replacing operation of a halogen lamp or the like as a light source are fully taken into consideration.
It is a further object of the present invention to provide a method for warming-up operating in the apparatus for evaluating the inner quality of vegetables and fruits in which the apparatus is subjected to the warming-up operation only for a sufficient period of time that required whereby the waiting time which is more than that required and is entirely wasteful is omitted while sufficiently securing the accuracy of measurement and evaluation to enable realization of the enhancement of operating efficiency and energy saving.
It is another object of the present invention to provide a method for measuring the inner quality in the apparatus for evaluating the inner quality of vegetables and fruits in which even if the kind and the breed of vegetables and fruits are variety, the inner quality can be measured efficiently while securing the sufficient measuring accuracy, and the apparatus constitution can be also simplified.
For achieving the aforementioned objects, an apparatus for evaluating the inner quality of vegetables and fruits according to the present invention comprises a place bed formed with a transmission light detecting hole and on which vegetables and fruits are placed; light sources disposed opposedly on both sides of the place bed to irradiate vegetables and fruits; a spectra/detection unit for making spectra in transmission light having transmitted through vegetables and fruits and passed through the transmission light detecting hole and detecting optical strength; an A/D converter for converting an analogue detection signal into a digital detection signal; an operation processing section for calculating and evaluating the quality evaluation amount of the sugar degree and the ripening degree on the basis of the detection signals; a measuring button for instructing the measurement; and a display panel for displaying the quality evaluation amount of the sugar degree and the ripening degree, the apparatus capable of being installed on the table, and also being portable.
Further, an apparatus for evaluating the inner quality of vegetables and fruits according to the present invention comprises a place bed formed with a transmission light detecting hole and on which vegetables and fruits are placed; light sources disposed opposedly on both sides of the place bed to irradiate vegetables and fruits; a spectra/detection unit for making spectra in transmission light having transmitted through vegetables and fruits and passed through the transmission light detecting hole and detecting optical strength; an A/D converter for converting an analogue detection signal into a digital detection signal; an operation processing section for calculating and evaluating the quality evaluation amount of the sugar degree and the ripening degree on the basis of the detection signals; a display panel for displaying the quality evaluation amount of the sugar degree and the ripening degree; and detection means for detecting whether or not vegetables and fruits are placed on the place bed, the apparatus capable of being installed on the table, and also being portable, wherein when the detection means detects that vegetables and fruits are placed on the place bed, the measurement is automatically started.
As the detection means, a position sensor or a weight sensor can be employed. Further, the strength of the transmission light can be measured preliminarily, and the detected optical strength can be compared. If a design is made so that when the placement of vegetables and fruits is detected, the measurement is automatically started, an operator is able to make measurement easily without troublesome operation, and the measuring time can be also shortened.
If a design is made so that the transmission light detecting hole and the spectra/detection unit are connected by optical fibers, it is possible to prevent the stray light from entering and to enhance the measuring accuracy, which is preferable.
If the place bed is formed with a fitting depressed portion on which vegetables and fruits are placed, and the fitting depressed portion is formed with a transmission light detecting hole extending to the bottom, vegetables and fruits can be held on the fitting depressed portion stably to enable positive measurement, which is preferable.
Further, if a holding material comprising a sponge rubber is installed on the fitting depressed portion of the place bed, it comes to close contact with vegetables and fruits due to the flexibility of the holding material to prevent the stray light from entering the transmission light detecting hole, thus enhancing the measuring accuracy, which is preferable.
If the spectra/detection unit is designed so that the transmission light having transmitted through vegetables and fruits is divided into a number of frequency areas to detect the optical strength of each frequency area, various quality evaluation amounts can be calculated from the optical strength of each frequency area, which is preferable.
If a shutter opening and closing device comprising a shutter for shielding light having passed through the transmission light detecting hole and a shutter driving device for moving the shutter is disposed, the measurement in the shield time can be automated, which is preferable.
If a transmission standard body setting device comprising a transmission standard body for transmitting light having passed through the transmission light detecting hole and a transmission standard body driving device for moving the transmission standard body is disposed, the measurement of the standard body can be automated, which is preferable.
Further, if a peripheral temperature of a light source is detected in a manner of a lapse of time, the peripheral temperature of a light source is compared with a safety setting temperature, and the fact that the light source temperature is completely lowered is reported, the replacing operation of the light source can be carried out safely and promptly.
Further, if an environment temperature is detected in a manner of a lapse of time, and the peripheral temperature of a light source is also compared with the environment temperature whereby the fact that the light source temperature is completely lowered is reported, it can cope with even the difference in the environment conditions such as the summer season, the tropical zone or the like.
A method for warming-up operating in an apparatus for evaluating the inner quality of vegetables and fruits according to the present invention comprises: automatically judging that a spectra of a light source is stabilized to decide the termination of the warming-up operation, and executing the warming-up operation till the termination of the warming-up operation.
Further, a method for a warming-up operating in an apparatus for evaluating the inner quality of vegetables and fruits according to the present invention comprises: automatically judging that a spectra of a light source is stabilized to decide the termination of the warming-up operation, executing the warming-up operation without operating a light source cooling fan till the termination of the warming-up operation, and operating the light source cooling fan after the termination of the warming-up operation.
Alternatively, the spectra of the light source is detected in a manner of a lapse of time, whether or not the spectra of the light source is stabilized is judged by the strength ratio of light or the strength difference of light of a fixed wavelength, and the termination of the warming up operation is decided.
Further, alternatively, the peripheral temperature of the light source is detected in a manner of a lapse of time, whether or not the spectra of the light source is stabilized is judged on the basis of the fact that the peripheral temperature is stabilized, and the termination of the warming-up operation is decided.
In a case where the peripheral temperature of the light source is detected in a manner of a lapse of time, a fixed time ts is added after the stabilization of the peripheral temperature to thereby decide the termination of the warming-up operation.
It is preferably confirmed that the strength of light having a fixed wavelength be within the allowable range to decide the termination of the warming-up operation.
A method for measuring the inner quality in an apparatus for evaluating the inner quality of vegetables and fruits according to the present invention comprises: preliminarily measuring the strength of light having reflected or transmitted through vegetables and fruits in a relatively short period of time before the inner quality of vegetables and fruits is measured really, setting the time for measuring the inner quality corresponding to the strength of light measured, measuring the strength of light having reflected or transmitted through vegetables and fruits in the measuring time set, and measuring the inner quality really.
Alternatively, a table corresponding the measuring time necessary in the real measurement to the strength of light measured in the preliminary measurement is set, the measured value of the strength of light is collated to the table, and the measuring time necessary in the real measurement is set.
Preferably, as the strength of light in the preliminary measurement, the strength of light having a fixed wavelength is employed.
Particularly, preferably, as the fixed wavelength, a wavelength within the range of 700xcx9c850 nm is employed.